Trains’ Checked Bags to Be Scanned. The federal government will start screening checked bags next week on five trains leaving from Union Station, the first time this airport-style security measure will be used to safeguard trains. Officials at the Transportation Security Administration said the experiment will last a month and is designed to find out whether screening checked bags is a useful way to protect against terrorist attacks on trains. TSA officials said bags would be screened by the same three-dimensional imaging machines that have been used at airports since the Sept. 11, 2001, terrorist attacks. Full Story